s corporation, what are the tax deadlines i should monitor each month, each quarter and each year?

Answer 1

Don't forget state income tax withholdings or state unemployment inusrance. Most UI returns are quarterly but you may find that you have to report tax withholdings on a monthly basis.

If you have a year-end other than 31st December, the due date for the 1120S is the fifteenth day of the third month after the year end.

Answer 2

S Corp. tax returns are due 3/15. If you file an extension, the tax returns are due 9/15.

Quarterly payroll tax returns (941s) are due as follows:

QE 3/31 due 4/30
QE 6/30 due 7/31
QE 9/30 due 10/31
QE 12/31 due 1/31

Form 940 (FUTA) due 1/31

You may need to file quarterly state payroll tax returns as well.
For sales tax, conform to your state deadlines.

Note to 'skip' below: All S-Corps must have a calendar (12/31) year end.